Anti-smog device



.9. 3K, 197 E. R. KNOPP ANTI-SMOG DEVICE 2 Sheets-Sheet 1 Filed June 14, 1965 IN VENTOR. EDWARD R: K NOPP B Y ATTORNEY Jan. 31, 1967 E. R. KNOPP ANTI-SMOG DEVICE Filed June '14, 1965 2 Sheets-Sheet 2 INVENTOR.

EDWARD R. KNOPP ATTORNEY United States Patent 3,300,964 ANTll-SMUG DEVICE Edward R. Knapp, 7884 Wyandot St., Denver, Colo. 80221 Filed June 14, 1965, Ser. No. 463,610 4 Claims. (Cl. 6tl3tl) The present invention relates to an anti-smog attachment for automobile exhausts and, more particularly, to an automotive exhaust gas contaminates reduction system.

The present apparatus is directed to the elimination of unburned hydrocarbons in the exhaust gases of automotive vehicles. A main purpose and objective is to reduce the quantity of unburned hydrocarbons and other deleterious substances discharged from the exhaust of automotive vehicles, so excess pollutants will not be accumulated in the atmosphere to cause smog conditions.

In accomplishment of such objective, it is an object of the invention to provide apparatus for inducing the burning of such materials before they are discharged from the exhaust.

Another object of the invention is to provide apparatus for the introduction of supplementary air to the exhaust stacks of an internal combustion engine in such manner as to obtain an efficient mixing of the air with unburned materials in the exhaust product of the engine to promote the burning of such materials.

The foregoing objects of the invention have been recog nized by others as a potential solutionfor the elimination of smog creating factors in the atmosphere of large communities. Accordingly, while it is the intent of the present invention to provide an air pollution control device that will satisfy the foregoing objectives, it is a further object of the invention to provide apparatus which will accomplish the desired purpose in a more efiicient manner to thereby further reduce the percentage of air pollution. It is also an overall objective to provide a mechanism that may be more economically installed and used on automotive equipment.

Specific objects of the invention include the provision of a mechanism which will efliciently intermix the exhaust gases and a suplementary quantity of make-up air in proper proportions to efliciently support the combustion of such unburned products.

Another object of the invention is to provide apparatus which uses the natural flow characteristics of gases to induce the eificient introduction and mixing of supplementary air to the exhaust system of an internal combustion engine.

A further object of the invention is to provide a combination of flow devices which conjointly contribute to the desired intermixing and burning without substantial increase in the back pressure for the exhaust system.

Further objects and advantages of the present invention will be apparent from the appended description and drawings, in which FIG. 1 is a side elevation illustrating the installation of components of a first embodiment of the invention in an automotive exhaust system,

FIG. 2 is an enlarged cross-sectional elevation of a first type of apparatus,

FIG. 3 is a partial cross-sectional elevation showing a separate embodiment of the invention, and

FIG. 4 is a side elevation in quarter-section illustrating the configuration for a tail pipe flow inducing apparatus used to reduce system back pressures.

Briefly stated, the present invention provides attachments for the exhaust system of an internal combustion engine so that a regulated quantity of make-up air under impact pressures may be introduced into the flow of exhaust gases from the engine to be intermixed therewith as necessary to induce the combustion of the unburned ice hydrocarbons included in the discharged exhaust gases. Separate embodiments of the invention are presented in which the desirable intermixing of the make-up impact air is accomplished in separate Ways. In a first embodiment of the invention the impact air is premixed with a minor quantity of separated or bleed exhaust gases before such intermixture is introduced in the main exhaust system for further intermixing with the main stream flow of exhaust gases. In the second embodiment of the invention the impact air is added directly to a separated component of exhaust gases and almost immediately further intermixed with the main exhaust system for further intermixing with the main stream flow exhaust gases. In all embodiments of the invention various channel shapes and flow guide elements are used to take advantage of gaseous stream flow characteristics to increase the efiiciency of introduction, mixing and discharge operations.

FIGURES 1 and 2 illustrate a first embodiment of the invention in which the anti-smog device 11 is applied in the exhaust system 12 of an internal combustion engine 13. As shown, the exhaust system may include a muflier 14 and a tail pipe 15 of conventional configuration as typically used in specific automotive vehicles. A tail pipe extension 16 is desirably provided for inclusion in the system when the anti-smog device 11 is used. As an addition to a conventional exhaust system, a make-up impact air tube 17 is shown in FIGURE 1. This impact tube 17 is provided with an entrance opening 18 which preferably is disposed toward the front of the automotive vehicle so that ram air will be received in the tube. The entrance opening may be positioned adjacent the bumper, radiator or other element of the vehicle so long as the opening 18 is disposed forwardly to receive free air under the influence of impact forces resulting from the forward movement of the vehicle.

The manner in which the impact make-up air is introduced to the exhaust system for the vehicle is further illustrated in FIG. 2. In this figure it will be seen that the anti-smog device 11 is applied to the outlet flange 19 of the exhaust header 22 for the engine 13. In order to make such installation on existing vehicles, a short length of exhaust pipe is removed, and the anti-smog device 11 is substituted so that the exhaust gases which normally would pass from the exhaust header 22 to the exhaust system 12 will be'constrained to flow through the anti-smog device 11. With the device 11 installed, a bleed pipe 23 is connected to the header 22 so a portion of exhaust gases from the engine 13 are extracted from the header 22 at a position above the flange 19 by the bleed system 23. This bleed pipe, which has an inner end 24 communicating with the exhaust gas flow through the header 22 is provided with a discharge end 26 which delivers a small quantity of bleed exhaust gases to a bounce or surge chamber 27. In such surge chamber the bleed exhaust gases will be premixed with the impact air delivered to such surge chamber by the impact tube 17. Preferably, the impact air is introduced in the surge chamber by a nozzle for-med outlet 28 connected to the surge chamber upstream from the point of introduction for the bleed gases. Opera-tion of the device has further shown that the flow characteristics can be improved if the impact air is introduced in the surge chamber at a restriction or vena in such chamber. Introduction at this point of reduced pressure not only provides for induced flow of the impact air but tends to further eliminate a back flow of exhaust gases into the impact tube due to the pulsing pressure pattern in the exhaust header 22 or in the bleed pipe 23.

In an efficient installation of the present type, a surge chamber that was approximately five feet in length has been provided. Use of such elongated surge chamber materially reduces the pulse pressure characteristics so that an even flow of premixed bleed gases and impact air is available for introduction into an external chamber 31 of the anti-smog device 11. From this external chamber the premixed materials are directed into the main exhaust flow channel which passes through a nozzle apparatus 32. The nozzle apparatus 32 provides a tapered entrance channel 33, a constriction or vena contractu 34 and an outlet flare segment 36. The premixed materials are introduced into such nozzle at the vena by passage through a diametrically disposed jet slot or aspirational orifice 37 provided by a roll pin 39 extending through the walls of the nozzle 32 and communicating directly with the chamber 31. Additional premixed gases are also introduced through the radially disposed slots 38 in the flared segment 36. Through use of these components the main flow exhaust gases and the premixed product will be efficiently intermixed downstream from the constriction 34, and if a proper temperature is maintained, combustion of unburned products in the exhaust gases will result.

Since it is recognized that the placement of the antismog device in the exhaust system will tend to increase the back pressure for the engine 13, it is desirable that a flare outlet 16 be provided on the exhaust system 12 so that the efliciency of discharge from the exhaust system will be increased and so that the increase of back pressure will be kept to a minimum. It should be noted that in order to provide maximum efficiency for this type of anti-smog device, it is necessary that the exhaust gases and the make-up air be efficiently intermixed one with the other so that all unburned products may be burned to eliminate the undesirable discharge from the exhaust for the engine. Some turbulence of stream flow is required at the point of intermixing, and it has been found that the reversed presentation for the nozzle 32 is desirable. With the nozzle disposed in what would ordinarily be considered a reversed direction, as illustrated, an efficient intermixing is obtained, and the unburned products may be efiiciently burned without the introduction of surplus quantities of air. Efficient mixing of reduced quantities of air, of course, prevents undue cooling of the exhaust gases so that a proper kindling temperature can be maintained when the anti-smog device is joined to the exhaust header 22 of an engine in position closely adjacent to the exhaust ports for the engine. Inasmuch as the outlet flange 19 for most exhaust headers on internal combustion engines is closer than shown in the present illustration, a device of the foregoing type can usually be connected directly to the outlet flange 19 for such engines.

A separate embodiment of the invention is shown in FIGURE 3. In this embodiment the overall operation is comparable to that previously described. However, in place of the extraction of a small quantity of bleed exhaust gases for premixture with the impact air by use of a separate bleed pipe, the present installation first separates a central flow of exhaust gases for premixture with the impact air, then intermixes the premixed product with the full stream flow of exhaust gases.

A suitable arrangement for this modified system, as shown in FIGURE 3, again uses an impact air entrance tube 17 which is connected directly to the anti-smog device 41. As in the previous embodiment, the impact air pickup may be disposed toward the front of the vehicle so that the air will be delivered under a slight pressure to the device 41. At the unit the air tube 17 is interconnected to an elbow or other fitting 32, which is threaded to a nipple 43 passing through the wall 44 of the smog device 41. The through nipple 43 is also secured interiorly of anti-smog device 41 to a pipe T 46, which is disposed with its cross axis aligned with the axis of fiow for the device 41, By tightening the fitting 42 against the seal collar 47, the orientation of the T within the device 41 may be established, and any leakage from the device will be avoided by the contact be tween the collar 47 and the fitting 42. With this arrangement a flow passage 48 is provided from the impact tube 17 through the fitting 42 and and the nipple 43 to the cross axis flow channel 51 of the T 46.

In order to separate a small quantity of the exhaust products and to intermix these separated gases with the incoming make-up impact air to provide a premixture of air and engine exhaust products, a separator guide cylinder 49 is provided interiorly of the cross axis flow channel 51. This guide cylinder 49 is provided with an entrance opening 52 disposed upstream of the T 46 and an outlet 53 that is downstream from the impact air introduction passage 48. In a preferred installation the downstream outlet 53 is positioned adjacent to a flow constriction 54 at the outlet of the cross axis channel 51. The described assembly is attained through use of a tapped fitting 56 which is threaded into the upstream end of the T 46 in such manner that the threads will provide for minor adjustments in the positioning of the outlet 53.

With this overall arrangement a portion of the impact air which is introduced through the openings 67 is premixed with the gaseous discharge flowing through the passage 57 in the guide cylinder 49. These premixed products can produce a preliminary combustion within the guide cylinder 49, or due to the pulsations in the system as induced by the impact air, or by the pulsing gaseous discharge from the valves of the internal combustion engine, some air might be introduced upstream from the entrance opening 52 to institute such precombustion of a portion of the impact air and the exhaust gas discharge. Whether combustion is started in the manner described or not, the premixed products will be expanded as they pass the constriction 54 to be discharged into the central flow area for the anti-smog device 41. Upon exit from the T 46 these premixed gases which will include a surplus of air for the quantity of entrained unburned products will be available for combustion and intermixture with the main flow of exhaust gases which pass exteriorly of the T structure 46 and are directed along a spiral path by guide vane 59 before being mixed with the premixed products from the T 46.

As illustrated, the guide vane 59 imparts a swirling motion to the exhaust gases, which materially increases the turbulence in the gas flow pattern downstream from T 46. This turbulence improves the intermixture of unburned hydrocarbons and the available oxygen in the impact air contributes to the full combustion of such unburned hydrocarbons.

While the separation functions and the premixing operations for the guide cylinder 49 might be dispensed with in the provision of a working apparatus, it has been found desirable in the operation of both embodiments of the invention to premix a small portion of exhaust gases with an excess of air before a second mixing step in which the premixed exhaust gases and air is mixed with the remainder of the exhaust gases. Apparently the provision of an excess of air in the premixed product contributes to better initial combustion and, accordingly, the temperature of the total gas flow is re-elevated so that combustion of the remaining unburned gases may proceed. With direct mixture of all make-up air and all exhaust gases, the temperature may be reduced below a proper burning or kindling temperature for the admixture.

As in the previous embodiment of the invention, it should be noted that flow guiding structures are used in order to accomplish the desired intermixing and also to reduce undesirable friction in the flow system. For these purposes the nozzle constriction 54 is provided at the outlet of the T segment 46, and the guide cylinder 49 is provided with tapered shapes in order to provide passages and outlets having minimum resistance to stream flow. As in the earlier embodiment, it is desirable that a tail pipe flow inducing extension 16 be provided at the outlet to the exhaust system 12 so that the back pressure acting against the engine will not 'be materially'increased by reason of the inclusion of the anti-smog device in the exhaust system.

Small structural features of a desirable type flow inducing tail pipe extension are shown in FIGURE 4. Here it is seen that the tail pipe extension 16 is provided with an upstream collar 61 which fits over the end of the exhaust tail pipe 15, and the collar 61 is formed so that the extension may be secured to the tail pipe 15 by means of a clamp and bolt 62. The extension itself provides a flared shape downstream from the tail pipe 15 so that the flow passage for the gases will be substantially expanded before the gases are exhausted from the system. This expansion of flow area together with the syphon eifect created by passage of surrounding air along the exterior curved face 63 and past the outlet edge 64 of the extension induces an increased flow out of the exhaust system 12 which reduces the overall back pressure for the system. As in the previous constructions, a constriction 66 is provided to increase the efficiency of gas flow.

It should be noted that the working parts of the device 41 could be provided as separate components to be inserted into the interior of an existing exhaust pipe which might even be bent at the point of installation. To effect such installation it would only be necessary to drill a threequarter inch hole in the wall of the pipe. Thereafter the T 46 would be placed within the pipe with the nipple extending through the opening, and a seal would be established between the pipe and such components by the collar 47 when the fitting 42 is tightened on the nipple 43. For such installation the collar 47 would necessarily be of a shape to fit tightly against the exterior surface of the exhaust pipe.

In the operation of this insert component or in the operation of a complete device as illustrated in FIGURE 3, it should be noted that a portion, which might be described as a bleed portion, of the exhaust gases are extracted from the main flow of such gases in a position upstream from the main components of said device and at the center of the device for movement through the passage 57. The central disposition for this point of extraction is believed to be of importance, since the carbon monoxide components in the exhaust gases which are of less density than most of the gases discharged by an internal combustion engine could be of higher percentage concentration at the center of any spirally moving flow pattern. Heat losses due to convection and radiation effects will likewise be reduced at such central location, and, accordingly, it is expected that the portion of exhaust gases introduced into the passage 57 will be at a high temperature, which will contribute to the efiiciency of any initial combustion.

Either of the embodiments of the invention incorporate an important safety feature, inasmuch as they provide a channel for the escape of exhaust gas products if the tail pipe or tail pipe extension 16 should at any time become clogged. Upon the happening of such event, exhaust gases could escape through the impact tube 17 to prevent excess leakage of such exhaust gases from the exhaust system that might accumulate in the passenger compartment of the vehicle.

While separate embodiments of the invention have been shown and described, it should be recognized that the principles of the invention are adaptable to various modifications and changes. All such modifications which come within the scope of the appended claims are considered as a part of this invention.

1 claim:

1. An anti-smog device for use on the exhaust system of internal combustion engines in position adjacent the exhaust valves thereof for inducing the more complete combustion of unburned products included in the heated gaseous discharge from said engine comprising a gaseous discharge flow conduit, a duct member disposed to extract a bleed portion of said gaseous discharge at a position upstream with respect to the main components of said device, a fiow constriction downstream therefrom, an air tube disposed to deliver a quantity of makeup air to said device, means within said device for introducing a part of said makeup air into said bleed portion of said discharge gases at a point upstream from said flow constriction, a chamber downstream from said point of introduction for the initial premixture or combustion of said unburned products, means for the introduction of the remainder of said makeup air in a zone ahead of said flow constriction for passage therethrough, and an outlet from said flow constriction disposed centrally of said flow conduit, whereby an oxygen ric-h mixture from said flow constriction is subsequently discharged centrally of the flow passage for said discharge gases and in the turbulence zone downstream from said flow constriction.

2. An anti-smog device for use on the exhaust system of internal combustion engines for vehicles in position adjacent the exhaust valves thereof for inducing the more complete combustion of unburned products included in the heated gaseous discharge from said engine comprising a gaseous discharge flow conduit, a duct member disposed to extract a bleed portion of said gaseous discharge at a position upstream with respect to the main components of said device, a flow constriction downstream therefrom, an impact air tube disposed toward the front of the vehicle to deliver a quantity of makeup air under super-atmospheric pressure to said device, means within said device for introducing a part of said makeup air into said bleed portion of said discharge gases at a point upstream from said flow constriction, a chamber downstream from said point of introduction for the initial premixture or combustion of said unburned produ'cts, means for the introduction of the remainder of said makeup air in a zone ahead of said flow constriction for passage therethrough, and an outlet from said flow constriction disposed centrally of said flow conduit whereby an oxygen rich mixture from said flow constriction is subsequently discharged centrally of the flow passage for said discharge gases and in the turbulence zone downstream from said flow constriction.

3. An anti-smog device for use on the exhaust system of internal combustion engines for vehicles in position adjacent the exhaust valves thereof for inducing the more complete combustion of unburned products included in the heated gaseous discharge from said engine comprising a gaseous discharge flow conduit, a duct member disposed to extract a bleed portion of said gaseous discharge at a position upstream with respect to the main components of said device, a flow constriction downstream therefrom and disposed centrally of said gaseous flow conduit, an impact air tube disposed at the front of the vehicle to deliver a quantity of makeup air under super-atmospheric pressure to said device, means within said device for introducing a part of said makeup air into said bleed portion of said discharge gases at a point upstream from said flow constriction, a chamber downstream from said point of introduction for the initial premix-ture or combustion of said unburned products, and means for the introduction of the remainder of said makeup air in a zone ahead of said flow constriction for passage therethrough whereby an oxygen rich mixture from said flow constriction is subsequently discharged centrally of the flow passage for said discharge gases and in the turbulence zone downstream from said flow constriction.

4. An anti-smog device for use on the the exhaust system of internal combustion engines for vehicles in position adjacent the exhaust valves thereof for inducing the more complete combustion of unburned products included in the heated gaseous discharge from said engine comprising a gaseous discharge fiow conduit, a duct member disposed to extract a bleed portion of said gaseous discharge at a position upstream with respect to the main components of said device, a flow constriction in the flow path of said duct member disposed downstream therefrom and centrally of said gaseous flow conduit, an air 'tube disposed to deliver a quantity of makeup air to said device, means within said device for introducing a part of said makeup air into said bleed portion of said discharge gases at a point upstream from said flow constriction, a chamber downstream from said point of introduction for the initial premixture or combustion of said unburned products, means for the introduction of the remainder of said makeup air in a zone ahead of said flow constriction for passage therethrough, and a spiral 15 8 from said flow constriction whereby the oxygen rich mixture from said flow constriction is discharged centrally of said gaseous discharge and in the spirally moving turbulence zone downstream from said flow constriction.

References Cited by the Examiner UNITED STATES PATENTS 1,370,197 3/1921 Bolotolf. 2,806,346 9/1957 Clayton 6030 2,851,852 9/1958 Cornelius 60-30 3,170,280 2/1965 Rees 6030 FOREIGN PATENTS 448,850 6/ 1936 Great Britain.

MARK NEWMAN, Primary Examiner.

RALPH D. BLAKESLEE, Examiner. 

1. AN ANTI-SMOG DEVICE FOR USE ON THE EXHAUST SYSTEM OF INTERNAL COMBUSTION ENGINES IN POSITION ADJACENT THE EXHAUST VALVES THEREOF FOR INDUCING THE MORE COMPLETE COMBUSTION OF UNBURNED PRODUCTS INCLUDED IN THE HEATED GASEOUS DISCHARGE FROM SAID ENGINE COMPRISING A GASEOUS DISCHARGE FLOW CONDUIT, A DUCT MEMBER DISPOSED TO EXTRACT A BLEED PORTION OF SAID GASEOUS DISCHARGE AT A POSITION UPSTREAM WITH RESPECT TO THE MAIN COMPONENTS OF SAID DEVICE, A FLOW CONSTRICTION DOWNSTREAM THEREFROM, AN AIR TUBE DISPOSED TO DELIVER A QUANTITY OF MAKEUP AIR TO SAID DEVICE, MEANS WITHIN SAID DEVICE FOR INTRODUCING A PART OF SAID MAKEUP AIR INTO SAID BLEED PORTION OF SAID DISCHARGE GASES AT A POINT UPSTREAM FROM SAID FLOW CONSTRICTION, A CHAMBER DOWNSTREAM FROM SAID POINT OF INTRODUCTION FOR THE INITIAL PREMIXTURE OR COMBUSTION OF SAID UNBURNED PRODUCTS, MEANS FOR THE INTRODUCTION OF THE REMAINDER OF SAID MAKEUP AIR IN A ZONE AHEAD OF SAID FLOW CONSTRICTION FOR PASSAGE THERETHROUGH, AND AN OUTLET FROM SAID FLOW CONSTRICTION DISPOSED CENTRALLY OF SAID FLOW CONDUIT, WHEREBY AN OXYGEN RICH MIXTURE FROM SAID FLOW CONSTRICTION IS SUBSEQUENTLY DISCHARGED CENTRALLY OF THE FLOW PASSAGE FOR SAID DISCHARGE GASES AND IN THE TURBULENCE ZONE DOWNSTREAM FROM SAID FLOW CONSTRICTION. 